Write a balanced chemical equation for the aqueous reaction between potassium hydroxide and hydrobromic acid. Include physical states. Question options: KOH (s) + HBr (g) ® H2O (l) + KBr (aq) KOH (s) + HBr (g) ® H2O (l) + KBr (s) KOH (s) + HBr (aq) ® H2O (l) + KBr (s) KOH (aq) + HBr (aq) ® H2O (l) + KBr (aq)
The Correct Answer and Explanation is:
The correct balanced chemical equation for the reaction between potassium hydroxide (KOH) and hydrobromic acid (HBr) in aqueous solution is:
KOH (aq) + HBr (aq) → H2O (l) + KBr (aq)
Explanation:
This is a typical acid-base neutralization reaction, where an aqueous base (KOH) reacts with an aqueous acid (HBr) to form water and an ionic salt (KBr).
- KOH is potassium hydroxide, a strong base. In an aqueous solution, it dissociates into K⁺ (potassium ions) and OH⁻ (hydroxide ions).
- HBr is hydrobromic acid, a strong acid. In water, it dissociates into H⁺ (hydrogen ions) and Br⁻ (bromide ions).
In a neutralization reaction, the H⁺ ions from the acid combine with the OH⁻ ions from the base to form H2O (water). The remaining ions, K⁺ and Br⁻, combine to form KBr, which is potassium bromide, a soluble ionic salt in water.
Physical States:
- KOH (aq) indicates that potassium hydroxide is dissolved in water, forming an aqueous solution.
- HBr (aq) indicates that hydrobromic acid is dissolved in water, also forming an aqueous solution.
- H2O (l) represents liquid water, the product formed from the neutralization.
- KBr (aq) indicates that potassium bromide is dissolved in water, forming an aqueous solution.
This reaction is exothermic, releasing heat as the ions form water.
